The present invention relates generally to an apparatus and method for comparison and evaluation of images of a material test specimen from NonDestructive Evaluation (NDE) and other sources. More particularly, the present invention relates to a method and apparatus for displaying similar images of a specimen on an interactive graphics display system and accurately locating and displaying locations in images which correspond to a selected location in one of the images.
Reliability of structural components can be achieved by accurate prediction of susceptibility to failure. Nondestrucutive evaluation by a method which has been shown to detect flaws in the material of which a structural member is composed is an effective method for achieving reliability of the structural member. Several NDE methods can be used to identify flaws which may cause failures of structural materials. Identification of the NDE method which most reliably identifies flaws that lead to failure is an important step in the development and application of structural materials.
Several NDE methods are used to evaluate materials. These include ultrasonic scans, radiography, X and gamma ray Computerized Tomography (CT), and Nuclear Magnetic Resonance (NMR) or Magnetic Resonance Imaging (MRI). Each of these methods is primarily sensitive to a single material characteristic. X-ray CT is primarily sensitive to density variations, NMR to chemical variations, and ultrasound to mechanical properties. To determine which of these methods may be most useful for predicting failure of a particular material, accurate comparison of images from the various NDE methods at the location of failure of a specimen is required. Because this type of comparison must be performed for a number of specimen, efficiency as well as accuracy of the comparison is desirable.
An interactive graphics display system can be used to identify specific locations in images of NDE specimens through use of the "Image-Pro" version 1.06 software. The method by which locations are identified using this software is to display an image on which a location of interest can be identified, obtain the distances from the location to identifiable specimen landmarks such as corners, display another image on which the location is to be identified and obtain distances from the identifiable landmarks to trial points until the location of interest is identified with acceptable accuracy This method provides adequate correlation and is acceptable for applications that require few locations to be correlated in a small number of images. The single image display and the trial and error method of locating points are disadvantages for applications that require many locations to be identified.
Therefore, in view of the above, it is an object of the present invention to provide an apparatus and method to evaluate a plurality of images of a material test specimen including NDE images by providing simultaneous accurate location by location correlation of the images.
It is another object of the present invention to provide an apparatus and method to evaluate a plurality of images from various NDE and other sources of a material test specimen that is efficient to implement and will allow rapid visual interpretation of the images.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.